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1.
BMC Musculoskelet Disord ; 25(1): 30, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167036

RESUMO

BACKGROUND: Total knee joint replacement (TKR) is an effective method for the treatment of severe knee osteoarthritis. With an increasing number of surgeries, complications such as lower limb edema, pain, and limited mobility have caused a heavy burden. Manual lymphatic drainage (MLD) may be a solution to solve the problem. The study aims to evaluate the efficacy of MLD in reducing knee edema, pain, and improving range of motion (ROM) in patients after TKR. METHODS: A search was conducted in PubMed, Embase, Cochrane Library, Web of Science, CNKI, VIPs, WanFang database, and Google Scholar from inception to June 2023. Only randomized controlled trials (RCTs) that compared the effects of MLD and non-MLD (or another physiotherapy) on improving knee edema, pain, and ROM after TKR were included. Stata 16.0 was used for meta-analysis. GRADE was used to assess the quality of evidence. RESULTS: In total, 7 RCTs with 285 patients were identified. There were no significant differences found in the ROM of knee flexion (standardized mean difference (SMD) = 0.03, 95% confidence interval (CI): -0.22, 0.28, P = 0.812) and the ROM of knee extension (SMD= -0.30, 95%CI: -0.64, 0.04, P = 0.084). No differences were observed in the lower extremity circumference after TKR (SMD= -0.09, 95%CI: -0.27, 0.09, P = 0.324). For postoperative pain, there was no significant advantage between the MLD and non-MLD groups (SMD= -0.33, 95%CI: -0.71, 0.04, P = 0.083). CONCLUSIONS: Based on the current evidence from RCTs, manual lymphatic drainage is not recommended for the rehabilitation of patients following total knee replacement.


Assuntos
Artroplastia do Joelho , Humanos , Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/reabilitação , Drenagem Linfática Manual , Ensaios Clínicos Controlados Aleatórios como Assunto , Edema/terapia , Dor Pós-Operatória
2.
Nanotechnology ; 35(1)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37797599

RESUMO

Fiber-shaped energy-storage devices for high energy and power density are crucial to power wearable electronics. In this work, reduced graphene oxide/carbon nanotubes/polypyrrole (GCP-op) cotton fabric with the optimal performance is prepared via a facile and cost-effective dipping-drying together with chemical polymerization approach. The structural characterizations confirm that the GCP-op cotton fabric has been successfully attached with numerous nanoparticles and carbon nanotubes, which can serve as a channel for electronical transfer. And GCP-op cotton fabric electrode displays admirable areal specific capacitance with 8397 mF cm-2at 1 mA cm-2. By combining GCP-op cathode with zinc anode, a GCP-op//PAM/ZnCl2//Zn flexible Zn-ion hybrid supercapacitor (FZHSC) is produced with 2 M polyacrylamide/ZnCl2(PAM/ZnCl2) hydrogel as the gel electrolyte. The FZHSC has superior cycle stability of 88.2%, outstanding energy density of up to 158µWh cm-2and power density at 0.5 mW cm-2. The remarkable performance proves that PPy-based material can provide more options for design and fabricate high energy flexible Zn-ion hybrid supercapacitors.

3.
BMC Urol ; 23(1): 1, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609237

RESUMO

OBJECTIVE: Urethral stenosis caused by pelvic fracture urethral injury (PFUI) is a complex urological disease, especially for the redo cased. However, to find the proximal end of the posterior urethra, and to avoid injury to the rectum and to forecast to remove the inferior pubic margin are two key points for a successful surgery. These steps can be challenging for even the most experienced urologists. This study is to describe a new technique for understanding the three-dimensional (3D) anatomy of the urethra, which will also aid in surgical planning and simplify urethroplasty. MATERIALS AND METHODS: Three patients underwent routine urethroscopy, X ray urethrography and contrast CT urethrography. The 3D images were then reconstructed, and the data were transmitted to a 3D printer. 3D models were printed with polyacrylic acid to simulate the anatomical structure and relationship of urethral stenosis with pubic symphysis and rectum. Various diagnosis methods were compared with the condition in surgery. The patients and trainee questionnaires were performed. RESULTS: Three models of urethral CT were obtained. These models were presented to patients and trainee doctors along with routine urethroscopy, urethrography, and urethral CT. The scores of patients and trainee question forms demonstrated that the 3D printed urethral stenosis model of pelvic fracture has obvious advantages in urethral adjacency and ease of understanding. The 3D printed urethras were easy to show the pubic symphysis and simulate its excision and exposure of urethra. The model could show the precise distance from urethra to rectum to prevent the rectum injury in surgery. CONCLUSIONS: 3D printing technology can be applied to the preoperative evaluation of urethral stenosis caused by PFUI. It can be auxiliary to understand the anatomical structure of the posterior urethra, the direction of urethral displacement, protecting the rectum and the forecasting for pubectomy. It is especially helpful for the accurate preoperative planning of some complex urethral stenosis and redo cases.


Assuntos
Fraturas Ósseas , Ossos Pélvicos , Estreitamento Uretral , Humanos , Uretra/diagnóstico por imagem , Uretra/cirurgia , Uretra/lesões , Estreitamento Uretral/diagnóstico por imagem , Estreitamento Uretral/etiologia , Estreitamento Uretral/cirurgia , Estudos Retrospectivos , Ossos Pélvicos/diagnóstico por imagem , Ossos Pélvicos/cirurgia , Ossos Pélvicos/lesões , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Fraturas Ósseas/complicações
4.
Molecules ; 28(22)2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38005397

RESUMO

Traumatic nerve defects result in dysfunctions of sensory and motor nerves and are usually accompanied by pain. Nerve guidance conduits (NGCs) are widely applied to bridge large-gap nerve defects. However, few NGCs can truly replace autologous nerve grafts to achieve comprehensive neural regeneration and function recovery. Herein, a three-dimensional (3D) sponge-filled nanofibrous NGC (sf@NGC) resembling the structure of native peripheral nerves was developed. The conduit was fabricated by electrospinning a poly(L-lactide-co-glycolide) (PLGA) membrane, whereas the intraluminal filler was obtained by freeze-drying a collagen-based matrix (ColM) resembling the extracellular matrix. The effects of the electrospinning process and of the composition of ColM on the physicochemical performance of sf@NGC were investigated in detail. Furthermore, the biocompatibility of the PLGA sheath and ColM were evaluated. The continuous and homogeneous PLGA nanofiber membrane had high porosity and tensile strength. ColM was shown to exhibit an ECM-like architecture characterized by a multistage pore structure and a high porosity level of over 70%. The PLGA sheath and ColM were shown to possess stagewise degradability and good biocompatibility. In conclusion, sf@NGC may have a favorable potential for the treatment of nerve reconstruction.


Assuntos
Regeneração Tecidual Guiada , Nanofibras , Nervo Isquiático , Nanofibras/química , Regeneração Tecidual Guiada/métodos , Colágeno/farmacologia , Alicerces Teciduais/química , Regeneração Nervosa
5.
Chaos ; 32(9): 093135, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36182379

RESUMO

Higher-order interactions have significant implications for the dynamics of competing epidemic spreads. In this paper, a competing spread model for two simplicial irreversible epidemics (i.e., susceptible-infected-removed epidemics) on higher-order networks is proposed. The simplicial complexes are based on synthetic (including homogeneous and heterogeneous) and real-world networks. The spread process of two epidemics is theoretically analyzed by extending the microscopic Markov chain approach. When the two epidemics have the same 2-simplex infection rate and the 1-simplex infection rate of epidemic A ( λ) is fixed at zero, an increase in the 1-simplex infection rate of epidemic B ( λ) causes a transition from continuous growth to sharp growth in the spread of epidemic B with λ. When λ > 0, the growth of epidemic B is always continuous. With the increase of λ, the outbreak threshold of epidemic B is delayed. When the difference in 1-simplex infection rates between the two epidemics reaches approximately three times, the stronger side obviously dominates. Otherwise, the coexistence of the two epidemics is always observed. When the 1-simplex infection rates are symmetrical, the increase in competition will accelerate the spread process and expand the spread area of both epidemics; when the 1-simplex infection rates are asymmetrical, the spread area of one epidemic increases with an increase in the 1-simplex infection rate from this epidemic while the other decreases. Finally, the influence of 2-simplex infection rates on the competing spread is discussed. An increase in 2-simplex infection rates leads to sharp growth in one of the epidemics.


Assuntos
Epidemias , Surtos de Doenças , Suscetibilidade a Doenças , Humanos , Cadeias de Markov
6.
Nanotechnology ; 32(50)2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34584021

RESUMO

Herein, we report an enhanced red emission from colloidal silicon nanocrystals (c-Si NCs) solution-processed light-emitting diode. c-Si NCs were synthesized by facile femtosecond laser ablation. Based on the structural characterization and opto-electrics properties analysis, both photoluminescence and electroluminescence arise from the radiative recombination of carriers due to quantum confined effect. The optical power density and highest external quantum efficiency have been obtained to be 0.79 mW cm-2and âˆ¼6.6%, respectively. These results indicate that Si NCs are very attractive as a potential optical source for future integrated chips.

7.
Nanotechnology ; 32(19): 195405, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33494075

RESUMO

Heteroatom-doped carbon materials with a high specific area, a well-defined porous structure is important to high-performance supercapacitors (SCs). Here, S and N co-doped three-dimensional porous graphene aerogel (NS-3DPGHs) have been synthesized in a facile and efficient self-assembly process with thiourea acting as the reducing and doping agent solution. Operating as a SC electrode, fabricated co-doping graphene, i.e. the sample of NS-3DPGH-150 exhibits the highest specific capacitance of 412.9 F g-1 under 0.5 A g-1 and prominent cycle stabilization with 96.4% capacitance retention in the back of 10 000 cycles. Furthermore, based on NS-3DPGH-150, the symmetrical supercapacitor as-prepared in 6 M KOH displays a superior energy density of 12.9 Wh kg-1 under the power density of 249 W kg-1. Hence, NS-3DPGHs could be considered as an excellent candidate for SCs.

8.
Nanotechnology ; 32(30)2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33878745

RESUMO

Polypyrrole (PPy) has high electrochemical activity and low cost, so it has great application prospects in wearable supercapacitors. Herein, we have successfully prepared polypyrrole/reduced graphene oxide (PPy/rGO) nanocomposite cotton fabric (NCF) by chemical polymerization, which exhibits splendid electrochemical performance compared with the individual. The addition of rGO can block the deformation of PPy caused by the expansion and contraction. The as-prepared PPy-0.5/rGO NCF electrode exhibits the brilliant specific capacitance (9300 mF cm-2at 1 mA cm-2) and the capacitance retention with 94.47% after 10 000 cycles. At the same time, the superior capacitance stability under different bending conditions and reuse capability have been achieved. All-solid-state supercapacitor has high energy density of 167µWh cm-2with a power density of 1.20 mW cm-2. Therefore, the PPy-0.5/rGO NCF electrode has a broad application prospect in high-performance flexible supercapacitor fabric electrode.

9.
Molecules ; 26(10)2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34069843

RESUMO

Optically active polymers are promising multifunctional materials with great application potentials. Herein, environmentally friendly optically active polyurethanes (OPUs) were obtained by introducing rotatory binaphthol monomer to polyurethane. The influence of binaphthol monomer content on the structure, mechanical properties, infrared emissivity, and thermal insulation of OPUs was studied intensively. Structure characterization indicated that the optically active polyurethanes have been successfully synthesized. The OPU synthesized with BIMOL and BDO at the mole ratio of 1:1 presented better thermal resistance. In addition, OPUs showed enhanced tensile strength and stretchability with the increase of BINOL content to a certain extent due to its rigid structural features and high molecular weight. The optically active polyurethanes showed lower infrared emissivity values (8-14 µm) than waterborne polyurethane (WPU), and the infrared emissivity decreased from 0.850 to 0.572 as the content of the BINOL monomer increased. Moreover, OPU4 exhibited the best heat insulation and cooling ability with about a 7 °C temperature difference. The thus-synthesized optically active polyurethanes provide an effective solution for developing highly effective thermal insulation materials.

10.
Eur J Clin Microbiol Infect Dis ; 39(9): 1771-1779, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32242313

RESUMO

Pentamidine sensitizes FDA-approved antibiotics to combat Gram-negative pathogens. We screened 1374 FDA-approved non-antibiotics for their ability to be sensitized by pentamidine against Escherichia coli. We identified mitomycin C and mefloquine as potent hits effective against multiple drug-resistant, Gram-negative bacteria. Killing kinetics and an in vivo model with Caenorhabditis elegans (C. elegans) revealed that such combinations produced synergy against colistin-resistant Enterobacter cloacae (E. cloacae). These findings suggest combinations of FDA-approved non-antibiotics, and pentamidine can be repurposed into new antimicrobial agents.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Pentamidina/farmacologia , Animais , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Caenorhabditis elegans/efeitos dos fármacos , Reposicionamento de Medicamentos , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Quimioterapia Combinada , Enterobacter cloacae/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Modelos Animais , Pentamidina/administração & dosagem , Pentamidina/uso terapêutico , Estados Unidos , United States Food and Drug Administration
11.
J Nanosci Nanotechnol ; 19(1): 263-267, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30327034

RESUMO

The new demands for energy storage systems have been placed with demands for flexible wearable electronics. Herein, rugby-like GeO2 nanoparticles (NPs) have been directly grown on carbon cloth (GeO2 NPs/CC) through a one-step hydrolysis process at room temperature, which can be used as a self-supporting flexible anode for lithium ion battery (LIBs). The rugby-like GeO2 NPs/CC showed an improved lithium-storage performance with features of high reversible capacity ~2000 mA·h·g-1 even after 100 cycles and good cycling stability. Besides, its initial coulomb efficiency (79.1%) was also enhanced compared to that of some reported GeO2-based materials.

12.
Bioconjug Chem ; 27(8): 1889-99, 2016 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-27418000

RESUMO

This study examined the ability of amphiphilic poly(ethylene glycol) (PEG) derivatives to assemble into micelles for drug delivery. Linear PEG chains were modified on one end with hydrophobic vitamin E succinate (VES), and PEG and VES were mixed in different molar ratios to make amphiphiles, which were characterized in terms of critical micelle concentration (CMC), drug loading capacity (DLC), serum stability, tumor spheroid penetration and tumor targeting in vitro and in vivo. The amphiphile PEG5K-VES6 (PAMV6), which has a wheat-like structure, showed a CMC of 3.03 × 10(-6) M, good serum stability, and tumor accumulation. The model drug, pirarubicin (THP), could be efficiently loaded into PAMV6 micelles at a DLC of 24.81%. PAMV6/THP micelles were more effective than THP solution at inducing cell apoptosis and G2/M arrest in 4T1 cells. THP-loaded PAMV6 micelles also inhibited tumor growth much more than free THP in a syngeneic mouse model of breast cancer. PAMV6-based micellar systems show promise as nanocarriers for improved anticancer chemotherapy.


Assuntos
Neoplasias da Mama/metabolismo , Portadores de Fármacos/química , Desenho de Fármacos , Polietilenoglicóis/química , Vitamina E/química , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Transporte Biológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Doxorrubicina/análogos & derivados , Doxorrubicina/química , Doxorrubicina/metabolismo , Doxorrubicina/farmacologia , Portadores de Fármacos/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Espaço Intracelular/metabolismo , Camundongos , Micelas , Esferoides Celulares/metabolismo , Vitamina E/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Mol Pharm ; 13(11): 3934-3944, 2016 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-27744704

RESUMO

Tumor cells can acquire multidrug resistance (MDR) as a result of drug efflux mediated by P-glycoprotein (P-gp). Here we report a targeted delivery system to carry pirarubicin (THP) to MDR breast cancer both in vitro and in vivo. PEG-derivatized vitamin E (PAMV6) amphiphiles loaded with THP were self-assembled in a single step. The PAMV6 micelles showed unimodal size distribution and high drug loading efficiency. Cytotoxicity of PAMV6/THP was higher than that of free THP on MCF-7/ADR cells but comparable to that of THP on MCF-7 cells. PAMV6/THP was able to reverse MDR more than free THP in MCF-7/ADR cells, likely reflecting the remarkably higher intracellular THP concentration in micelle-treated cells and PAMV6-mediated inhibition of P-gp activity. PAMV6/THP micelles were internalized into MCF-7/ADR cells via macropinocytosis and caveolin-mediated endocytosis, further avoiding P-gp-mediated efflux. Mechanistic studies revealed that blank PAMV6 micelles inhibited P-gp activity but did not affect P-gp expression, by significantly reducing mitochondrial membrane potential and slightly decreasing intracellular ATP levels. In a nude mouse xenograft model, PAMV6/THP led to much greater THP accumulation in tumors and much slower tumor growth than free THP. At the same time, PAMV6/THP was associated with significantly less severe bone marrow suppression and organ toxicity than free THP. Our results indicate that this PAMV6-based micelle system holds promise for combating MDR in cancer therapy.


Assuntos
Doxorrubicina/análogos & derivados , Micelas , Trifosfato de Adenosina/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Humanos , Células MCF-7 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Nus , Ratos , Ratos Wistar
15.
Heliyon ; 10(10): e31335, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38813190

RESUMO

Background: The erector spinae plane block (ESPB) was proposed as a part of the postoperative multimodal analgesic regimen to improve pain management after posterior spinal surgery. However, ESPB might cause more surgical incisional wound exudate and poor wound healing, which might be improved after topical lyophilized thrombin application. Materials and methods: We performed a retrospective study on patients who received posterior spinal surgery between January 2018 and December 2021. These patients were assigned into three groups: group A (general anesthesia), group B (general anesthesia with ESPB), and group C (general anesthesia with ESPB and topical 1000-unit thrombin application). Postoperative outcomes, including times of dressing changes, duration of suture removal, and incisional wound healing, were compared among these groups. Results: Our study included 89 patients, with 48, 20, and 21 patients in groups A, B, and C, respectively. Baseline demographics, height, weight, comorbidities, and operation duration were comparable among the three groups. Group B required statistically significantly more dressing changes and had a prolonged duration of suture removal than group A (9.4 ± 4.7 versus 6.5 ± 2.0 times, 16.2 ± 3.7 versus 14.2 ± 1.4 days, respectively), which could be statistically significantly improved after the thrombin application in group C. Group B also had more frequent poor wound healing (25.0 %), which could also be improved after the thrombin application (0.0 %). Conclusions: ESPB could cause more dressing changes and poor surgical wound healing after posterior spinal surgery, which could be improved by topical lyophilized thrombin powder application.

16.
J Hazard Mater ; 465: 133239, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38118202

RESUMO

In this study, we used soils with different pollution and nutrient levels (non-polluted S1, highly polluted low-nutrient S2, and highly polluted high nutrient S3) around the gold mine tailing ponds, and combined with metabolic limitation modeling and macro-genomics approaches, aiming to investigate the relationship between soil microbial composition and soil eco-chemometrics characteristics under heavy metal stress. The results showed that heavy pollution resulted in reduced SOC, TN, microbial biomass, and with C- and P- acquisition (BG, CBH, ALP) as well as nitrogen limitation of soil microbial metabolism in soils (S2, S3). Further analysis by macrogenomics showed that heavy metal contamination led to an increase in α-microbial diversity and altered the composition of microbial communities in the soil. The cycling of C, N, and P nutrients was altered by affecting the relative abundance of Anaeromyxobacter, Steroidobacter, Bradyrhizobium, Acidobacterium, Limnochorda (predominantly in the Ascomycetes and Acidobacteria phyla), with the most pronounced effect on the composition of microorganisms synthesizing C-acquiring enzymes, and heavy metals and pH were the main influences on ecological stoichiometry. The results of this study are useful for understanding the sustainability of ecological remediation in heavy metal contaminated areas and for developing ecological restoration strategies.


Assuntos
Metais Pesados , Microbiota , Poluentes do Solo , Solo/química , Ouro/análise , Metais Pesados/análise , Biomassa , Microbiologia do Solo , Poluentes do Solo/análise
17.
J Phys Condens Matter ; 36(26)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38537284

RESUMO

Supercapacitors (SCs) have become one of the most popular energy-storage devices for high power density and fast charging/discharging capability. Polyaniline is a class of conductive polymer materials with ultra-high specific capacitance, and the excellent mechanical properties will play a key role in the research of flexible SCs. The synergistic effect between polyaniline and graphene is often used to overcome their respective inherent shortcomings, thus the high-performance polyaniline-graphene based nanocomposite electrode materials can be prepared. The development of graphene-polyaniline nanocomposites as electrode materials for SCs depends on their excellent microstructure design. However, it is still difficult to seek a balance between graphene performance and functionalization to improve the weak interfacial interaction between graphene and polyaniline. In this manuscript, the latest preparation methods, research progress and research results of graphene-polyaniline nanocomposites on SCs are reviewed, and the optimization of electrode structures and performances is discussed. Finally, the prospect of graphene-polyaniline composites is expected.

18.
Adv Sci (Weinh) ; 11(2): e2302574, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37973550

RESUMO

The nasty urine microenvironment (UME) is an inherent obstacle that hinders urethral repair due to fibrosis and swelling of the oftentimes adopted hydrogel-based biomaterials. Here, using reduced graphene oxide (rGO) along with double-freeze-drying to strengthen a 3D-printed patch is reported to realize scarless urethral repair. The sodium alginate/gelatin/reduced graphene oxide (SA/Gel/rGO) biomaterial features tunable stiffness, degradation profile, and anti-fibrosis performance. Interestingly, the 3D-printed alginate-containing composite scaffold is able to respond to Ca2+ present in the urine, leading to enhanced structural stability and strength as well as inhibiting swelling. The investigations present that the swelling behaviors, mechanical properties, and anti-fibrosis efficacy of the SA/Gel/rGO patch can be modulated by varying the concentration of rGO. In particular, rGO in optimal concentration shows excellent cell viability, migration, and proliferation. In-depth mechanistic studies reveal that the activation of cell proliferation and angiogenesis-related proteins, along with inhibition of fibrosis-related gene expressions, play an important role in scarless repair by the 3D-printed SA/Gel/rGO patch via promoting urothelium growth, accelerating angiogenesis, and minimizing fibrosis in vivo. The proposed strategy has the potential of resolving the dilemma of necessary biomaterial stiffness and unwanted fibrosis in urethral repair.


Assuntos
Alginatos , Grafite , Alicerces Teciduais , Humanos , Alicerces Teciduais/química , Alginatos/química , Gelatina/química , Biomimética , Materiais Biocompatíveis/química , Fibrose , Regeneração
19.
J Biotechnol ; 385: 65-74, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38503366

RESUMO

Ethyl carbamate (EC), a multisite carcinogenic compound, is naturally produced from urea and ethanol in alcoholic beverages. In order to reduce the content of EC in wine, the accumulation of arginine in Saccharomyces cerevisiae was regulated by genetic modifying genes involved in arginine transport and synthesis pathways to reduce the production of urea. Knockout of genes encoding arginine permease (Can1p) and amino acid permease (Gap1p) on the cell membrane as well as argininosuccinate synthase (Arg1) respectively resulted in a maximum reduction of 66.88% (9.40 µg/L) in EC, while overexpressing the gene encoding amino acid transporter (Vba2) reduced EC by 52.94% (24.13 µg/L). Simultaneously overexpressing Vba2 and deleting Arg1 showed the lowest EC production with a decrease of 68% (7.72 µg/L). The yield of total higher alcohols of the mutants all decreased compared with that of the original strain. Comprehensive consideration of flavor compound contents and sensory evaluation results indicated that mutant YG21 obtained by deleting two allele coding Gap1p performed best in must fermentation of Cabernet Sauvignon with the EC content low to 9.40 µg/L and the contents of total higher alcohols and esters of 245.61 mg/L and 41.71 mg/L respectively. This study has provided an effective strategy for reducing the EC in wine.


Assuntos
Proteínas de Saccharomyces cerevisiae , Vinho , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Vinho/análise , Uretana/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Arginina/metabolismo , Etanol/metabolismo , Ureia/metabolismo , Fermentação
20.
J Colloid Interface Sci ; 649: 279-289, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37348347

RESUMO

Due to the rapid growth of electronic equipment technology, efficient electromagnetic shielding materials are needed for equipment and human protection. Among them, foam shielding materials with absorption as the primary mechanism have higher application value than highly reflective materials. Highly absorbing shielding materials can reduce the secondary pollution caused by electromagnetic wave reflection. In this study, we added Fe3O4@Polyvinyl alcohol (Fe3O4@PVA) and graphene oxide@silver (GO@Ag) into the polyurethane (PU) matrix and constructed Fe3O4@PVA and GO@Ag/PU composite foam by foaming. Fe3O4@PVA and GO@Ag form an excellent network structure in the PU foam skeleton, significantly improving its electromagnetic shielding effectiveness (EMI SE) and mechanical properties. The shielding effectiveness reached 30.9 dB with a specific EMI SE (SSE) of 274.9 dB × cm3 × g-1 at a Fe3O4@PVA filling of 7 wt%, where the electromagnetic wave absorption accounted for more than 80 % of the total EMI SE, proving absorption as the primary shielding mechanism. The results show that Fe3O4, as a ferromagnet, has both the dielectric loss of ferroelectric materials and the hysteresis loss of ferromagnetic materials in electromagnetic shielding, effectively improving the wave absorption performance of composite shielding materials. Therefore, this work provides a promising idea for efficient and lightweight wave-absorbing shielding materials in aerospace, portable electronic devices and lightweight wearable devices.

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